1. In 1638 the Italian scientist Galileo Galilei
and his assistant conducts an experiment to
measuring the speed of light. They settled down
in the hills, a few kilometers apart
the other. The assistant opened his headlight window
and, when Galileo observed his light, he opened
the window of his lantern.
a) The speed of light is 300,000 km/s.
The distance between the two hills is 3 km.
Choose the time you would mark in this
experiment and circle it.
10 seconds
1 second
1/1000 of a second
1/100,000 of a second
b) Can you tell this time with your eyes?
Explain your answer.
c) How far apart must the two observers be to distinguish the time of 1 second?
